John Lott's Response to Tim Lambert

Tim Lambert has written a critical review of my research that he has posted at his web site. The main claims that he makes are that I have not shown that concealed handgun laws increase gun possession and that they have not reduced crime. Much of what he writes involves misquoting of different sources. Take the two research papers that Lambert discusses by William Bartley and Mark Cohen as well as Florenz Plassmann and Nicolaus Tideman. My guess is that these authors would not recognize their research from the way Lambert describes them. William Bartley and Mark Cohen actually "found strong support for the hypothesis that the right-to-carry laws are associated with a decrease in the trend in violent crimes."1 I don’t know if Lambert realizes this, but the test Bartley and Cohen perform is strongly biased towards not finding a result and it is quite remarkable that they found the level of support that they did for the change in trends.2 Bartley has another piece in Economic Letters where he describes how his paper with Cohen provides "strong support" for the deterrence hypothesis.3 Florenz Plassmann and Nicolaus Tideman conclude that their results "indicate that more guns generally lead to fewer rather than more murders, and that it would be wrong to dismiss right-to-carry laws on the ground that more guns mean more danger, without considering their discouraging effect on potential murders."4

While I am not going to take the time to respond to all the claims, I have written up a short response to Lambert’s central claims.


1) Do right-to-carry laws significantly reduce the robbery rate?

  • "Was there substitution from violent crime to property crime? Lott found that the laws were associated with an increase in property crime . . . . Lott argues that this change occurred because criminals respond to the threat of being shot while committing such crimes as robbery by choosing to commit less risky crimes that involve minimal contact with the victim. Unfortunately for this argument, the law was not associated with a significant decrease in robberies. In fact, when data for 1993 and 1994 was included, it was associated with a small (not statistically significant) increase in robberies. The law was associated with a significant reduction in assaults, but there does not seem to be any reason why criminals might substitute auto theft for assault." Tim Lambert, "Do more guns cause less crime?" from his posting on his web site at the School of Computer Science and Engineering, The University of New South Wales (http://www.cse.unsw.EDU.AU/~lambert/guns/lott/)
  • All the preceeding quotes are based on not recognizing that a law can be associated with reduced crime even when the average crime rate in the period after the law is the same or higher than the average crime rate before the law. For example, look at the three diagrams in Figure 1. The first two figures show dramatic changes in crime rates from the law, but very different before-and-after average crime rates. In the first diagram, the average crime rate after the law is lower than the average crime rate before it, while the reverse is true in the second figure. The second figure corresponds to an example where the simple variable measuring the average effect from the law would have falsely indicated that the law actually "increased" the average crime rate, where in actual fact the crime rate was rising right up until the law passed and falling thereafter. If I had another figure where the inverted "V" shape was perfectly symetrical, the before and after averages would have been the same.

    The third diagram illustrates the importance of looking at more than simple before-and-after averages in another way. A simple variable measuring the before-and-after averages would indicate that the average crime rate "fell" after the law was adopted, yet once one graphs out the before and after trends it is clear that this average effect is quite misleading -- the crime rate was falling until the law went into effect and rising thereafter.


    2) Did the passage of right-to-carry laws result in more guns being carried in public places?

  • "Perhaps by ‘more guns,’ Lott means more guns carried in public places. However, surveys indicate that 5-11% of US adults admit to carrying guns, dwarfing the 1% or so of the population that obtained concealed-weapon permits. . . . And if those who got permits were merely legitimating what they were already doing before the new laws, it would mean there was no increase at all in carrying or in actual risks to criminals. One can always speculate that criminals' perceptions of risk outran reality, but that is all this is--a speculation. More likely, the declines in crime coinciding with relaxation of carry laws were largely attributable to other factors not controlled in the Lott and Mustard analysis." Tim Lambert, "Do more guns cause less crime?" from his posting on his web site at the School of Computer Science and Engineering, The University of New South Wales (http://www.cse.unsw.EDU.AU/~lambert/guns/lott/)


  • The survey results mentioned by Lambert refer to all transportation or carrying of guns by Americans. It includes not only carrying concealed handguns (whether legally or illegally) but also people who have a gun with them to go hunting or who may simply be transporting a gun between residences. On the other hand, any survey that focused solely on the illegal carrying of concealed handguns prior to the adoption of the law would find it difficult to get people to admit that they have been violating the law.

    The one percent figure he picks for carrying concealed handguns is also misleadingly low. Permitting rates depend upon many factors (such as the level of fees and the amount of training required), but they also depend crucially on the number of years that the permitting rules have been in effect. The longer the amount of time that the rules are in effect the more people who obtain permits. Everyone who will obtain permits does not apply for them immediately. With the large number of states that have only recently granted permits to people it is misleading to think that this tells us the rate at which people in those states will be carrying concealed handguns even a few years from now.

    Given how extremely law-abiding these permit holders tend to be, it seems doubtful that most people carrying concealed handguns with permits were illegally carrying a concealed handgun before the passage of the right-to-carry law. In many states illegally carrying a concealed weapon would be the type of violation that would prevent people from ever even getting a permit. There is no evidence that these permit holders have violated this particular law.

    Finally, while the evidence linking between the rate at which permits are issued and the drops in crime rates is important, it is only one portion of the evidence. For example, if there was no change in the number of people carrying concealed handguns, why did violent crime rates in neighboring counties without the law increase at the same time that they were falling in neighboring counties with the right-to-carry law?


    1. William Bartley and Mark Cohen, "The Effect of concealed Weapons Laws: An Extreme Bound Analysis," Economic Inquiry (April 1998): p. 259.

    2. Isaac Ehrlich and Zhiqiang Liu, "Sensitivity Analyses of the Deterrence Hypothesis: Let's Keep the Econ in Econometrics," Journal of Law and Economics, April 1999.

    3. William Alan Bartley, "Will Rationing Guns Reduce Crime?" Economics Letters, Vol. 62, 1999, pp. 241-243.

    4. Florenz Plassman and T. Nicolaus Tideman, "Does the right to Carry Concealed handguns Deter Countable Crimes? Only a count Analysis Can Say," State University of New York at Binghamtom working paper, May 19, 1999, p. 22.

    5. Another survey by gun control advocates claim that "four million legal handgun owners sometimes carried guns for protection 'in connection with work.' Two-thirds of those who carried handguns said they kept them in their vehicles, while the others said they sometimes carried them. . . . The researchers said about 56 percent of those who carried handguns outside of work did so fewer than 30 days per year, while 22 percent said they rarely left home without a gun." Will Hacker, "Majority of Owners Cite Security Concerns," South Bend Tribune, June 29, 1997, p. A6.

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